XR16L784_08 Datasheet, PDF (5/51 Pages) Exar Corporation – HIGH PERFORMANCE 2.97V TO 5.5V QUAD UART

REV. 1.2.3
Pin Descriptions
NAME
TX3
PIN #
28
RX3
21
RTS3#
26
CTS3#
22
DTR3#
27
DSR3#
23
CD3#
24
RI3#
25
ANCILLARY SIGNALS
XTAL1
50
XTAL2
49
TMRCK
31
ENIR
32
RST#
16/68#
VCC
GND
20
19
9,30,52
10,29,51
XR16L784
HIGH PERFORMANCE 2.97V TO 5.5V QUAD UART
TYPE
DESCRIPTION
O ^{UART channel 3 Transmit Data or infrared transmit data. Normal TXD output}
idles HIGH while infrared TXD output idles LOW.
I ^{UART channel 3 Receive Data or infrared receive data. Normal RXD input}
idles HIGH while infrared RXD input idles LOW. In the infrared mode, the
polarity of the incoming RXD signal can be selected via FCTR bit-4. If this bit
is a logic 0, a LOW on the RXD input is considered a mark and if this bit is a
logic 1, a HIGH on the RXD input is considered a space.
O UART channel 3 Request to Send or general purpose output (active low).
See description of RTS0# pin.
I UART channel 3 Clear to Send or general purpose input (active low).d. See
description of CTS0# pin.
O UART channel 3 Data Terminal Ready or general purpose output (active low).
See description of DTS0# pin.
I UART channel 3 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
I UART channel 3 Carrier Detect or general purpose input (active low).
I UART channel 3 Ring Indicator or general purpose input (active low).
I Crystal or external clock input. Caution: this input is not 5V tolerant.
O Crystal or buffered clock output.
I 16-bit timer/counter external clock input.
I Infrared mode enable (active high). This pin is sampled during power up, fol-
lowing a hardware reset (RST#) or soft-reset (register RESET). It can be
used to start up all 8 UARTs in the infrared mode. The sampled logic state is
transferred to MCR bit-6 in the UART.
I Reset (active low). The configuration and UART registers are reset to default
values, see Table-15.
I Intel or Motorola data bus interface select. HIGH selects Intel bus interface
and LOW selects Motorola interface. This input affects the functionality of
IOR#, IOW# and CS# pins.
+5V or +3.3V supply, all inputs are 5V tolerant except for XTAL1.
Power supply common, ground.
NOTE: Pin type: I=Input, O=Output, IO= Input/output, OD=Output Open Drain.
5